The U.S. Army Corps of Engineers is only allowing until April 30 for people to comment on the proposed open-pit copper and gold mine near the Bristol Bay region of southwest Alaska that supports the largest sockeye salmon fishery in the world.

Public hearings scheduled for Anchorage, Homer and Dillingham, where opposition to the mine is especially high, won’t have microphones. People will have to submit comments by computer, in writing or with a court reporter.

The company behind the proposed Pebble Mine is Northern Dynasty Materials Ltd. of Vancouver which has been proposing the mine for more than a decade. Tom Collier, the CEO of the subsidiary that would build the mine, was chief of staff at the Interior Department under Bill Clinton.

“In my view, participation in the Pebble Project would be the antithesis of sustainable business practices and could create undue risk to the long-term value of the Fund’s investments in First Quantum Minerals and to the sustainability of the Bristol Bay region,” DiNapoli wrote.